Conventionally, as a tapered multifilament line made of a plurality of filaments and having nonuniform thickness, there has been known, for example, a tapered multifilament yarn in which some of the plurality of filaments, are cut away halfway in the longitudinal direction toward an end of the yarn to reduce the thickness of the yarn in the longitudinal direction, and the remaining filaments are used as the yarn core (see, for example, Japanese Patent Application Laid-Open Publication No. 8-289708, hereinafter referred to as “Prior art 1”).
This prior art 1 has a problem of impaired smoothness of a yarn especially in the cut site, causing the yarn to be easily caught on a scrag, reducing the slipperiness between the yarn and the guide of a fishing rod due to increased frictional resistance, or making the line tend to be cut. Further, there has also been another problem of poor operating efficiency because a braiding machine used to produce the tapered line has to be stopped during braiding for cutting away a certain number of filaments for reducing the diameter of the line.
In order to solve the above-mentioned problems, there has been proposed a tapered multifilament yarn formed by drawing a multifilament or a yarn into a tapered shape (see Japanese Patent Application Laid-Open Publication No. 2002-339184, hereinafter referred to as “Prior art 2”). The thickness of this tapered multifilament yarn is changed in the longitudinal direction by changing the take-over speed relative to the feed speed of the filament while the drawable multifilament is drawn.
This prior art 2 has an advantage that the tapered multifilament yarn is excellent in smoothness because the filament has no cut site, the yarn having considerable durability because of the good slipperiness between the yarn and the guide of a fishing rod, and the like. Further, the yarn can be produced easily and efficiently because there is no need to cut away any filament. Also, any degree of tapering can be set by adjusting the drawing rate of the filament.